Detergent composition



Patented June 24, 1952 STATES PATENT OFFICE DETERGENT ooMPosrrIoN HerBextIhSandI-s, PhillipsburgNl I., and Wil- 11am: Ji Maxcy; Easton, Pa., as''sig'l'loiffsl to' Genji eraldnilifue at' Film Corporation, New York; Nay., alcorporation of Delaware 3l Claims;

This invention` relatesto novel' detergent conrpositions, comprising* essentiallyl a' mixture of" a non-ionic polyglycol" otherV type of"A detergent; a` solid alkali' metal hydroxidevandfa minoram'ount of thiourea.

ManyA cleaning compositions" havev beenl sugL gested comprising a mixture' of aV synthetic organic detergent and an` alkalii metal hydroxide.` Among the synthetic organic detergents which have been employed* at times inu such'- mixturesn are polyglycol' ether' type detergents o'f the type disclosed' inUi S; PatentiN. 119701578 and par tieularly the polyglycol others' of'alkyl? phenols of the type disclosed" in Ui S. Patent No', 2i2l3,477`. Ithas beenfound, however; that when synthetic organic detergentsv ofi' the polyglycolf ether type are mixed withF solid" alkali' metal" hydroxides a markeddarkening of color" results. This dark'- ening is-v particolari'y' pronounced withJ the polyglycol ether type'. detergents obtained fromy alkyl phenols; i. e: those' off'tietymty disclosed inU; Si Patent No. 2,213,471 However", this same dini culty is encountered tdsorne extentwiti" practically all polyglycoln ether-typedetergentsl when they are stored: in' contact"y with caustic alliales ina solid state;

I have now' discovered' that if theipolyglycol other` type detergent is mixed with` a small amount (about 10% `V by" weight?" of` thiourea, little or nodiscolorationoccurs, even afterprolonged storing when the polyglycol ethertype detergent containing, the thiourea is mixedwith and stored in contactwitheaustic alkalies; ii e. sodium or potassium hydroxide.'

For example; a'v mixtureiofi' 95'l parts byweiglit of sodium hydroxide-in" chip ori'flakeform with 5 parts by Weight' off a Water' solubleiethylene oxide condensation product* of' diamyl phenol; obtained by oondensin'gab'out" ldm'ol's of' ethylene oxide with one l molanproportion"ofv diamyl plie`- no1, as described in" said-l 'U5 S'. Patentf No: 2,2 13,477, was* foundzi to-` bef an excellent degreasing agentformetall However; onstandingovernight at room temperature the mixture changed from almost colorlessto a1 deepred shade. When this same polyglycolv etIiertypedetergent, obtained' by condensingethylene oxide Wthdiarnyl phenol, Was-mixedwithA of"`it`swei`ght` of thioureaA and' then added to theoausticfsoda` in the samefwayiby'mixing-soi as; to forrnla'tiiinflln' NoLDxfawing. Application` December: 311,11948,` Serial-` N0. 683724 around' the solid particles; it wasL found that there was little; il." any; discoloration' even after several Weeks" storage. At' the same time the mixture retainedv full'` effectiveness as a` degreasing agentfor metal; Similarl results were obtained when 1lotassilim4` hydroxide was-used in placefof the sodium hydroxide in the above comu positions.

The' cause` olj this' discoloration on storing a polyglycol ethertyp'e detergent in' contact with a solid alkali is not clearly understood; It is possible thatitmay be connected with` air oxidation, but n'o conclusive' evidence that this is so has been found; and I therefore do notv wish to` be held to" any theory ofi operation, particularly sincethiourea appears' tobe unique in' its stabiliz'ing action among a Widev variety` ofV known anti-oxidants which have" been tested; Thus,` such" materials assodum" sulfite, itaconic acid and ascorbie: acid have been tested as well as tl'ilourea, but of these` onlyfthioureaproved to be effective:

The thioure'a' can" be" dissolved l directly in" an-` hydrouspolyglycolether type' detergents and the modifiedi detergent oan'then be storedn contact with alkali metal'hydroxid'es. The`-`^re1ative proportionsv of po1y',';lyco1 ether" type detergent' and solidAv alkaliido not" formL a critical feature of the present invention since" the discoloration has beenV fourniV tcoccur in substantially allv proportions; and" thiourea been found to be eiiective in preventing this; discoloration" in the mixtures* off` polygly'col other type detergents and solid"alka1ies^in Wide variety of f proportions, i.j e. fromf mixtures containing 1%" polygly'coll ether type detergents; toimix'tures containing 501%? or higher polyglycol other type detergents. The amount" of tliioureal which should beincorporated: inthe polyglycol-ether type` detergent to eiiect ther maximum color stabilization' can readilyu be determined for any particular" ocmpositionbyfsimple"prelininary'tests. Ingenera'l, tuo noaxilmu'm` c'olorstldilzauon appears `to be obtainedWheny from 5to' 10 "725v of thiourea,` based on thevveight" of thepoly'glycol. ether. type detergent; is used."`

Bythe terl'n polyglfycol'ethen type. detergent, .I mean the" nonlonic surface active` agents` obtainedbry "condensing alkylene oxides with Water ihso'hibl orgalib" compounds c'Olita'ili'ng4 at least 6 carbon atoms and having an active hydrogen, such as organic hydroxy compounds, (i. e. alcohols, phenols); primary and secondary amines; amides (carboxylic and sulfonic acid amides) and organic carboxylic and sulfonic acids. Compounds of this type are well known in the art and are disclosed, along with suitable methods for their preparation, in U. S. Patents Nos. 1,970,578 and 2,213,477. They may be represented by the following general formula:

-CHRLCHRLOLH R wherein R represents the residue of an organic compound containing an active hydrogen and the R' represents hydrogen or lower alkyl andra represents an integer of from 3 to 100 or higher, and usually from 6 to 50. These compounds may readily be obtained as disclosed in the above mentioned patents by condensing a polyglycol ether containing the required number of alkenoxy groups or an alkylene oxide, usually ethylene oxide (although propylene or butylene oxides may be employed if desired) with a water insoluble organic compound containing at least 6 carbon atoms and having an active hydrogen. The amount of alkylene oxide condensed with the water insoluble organic compound having an active hydrogen, i. e. the length of the polyglycol ether chain, will depend primarily on the particular compound with which it is condensed. As a convenient rule of thumb, approximatelyl mol of alkylene oxide should be employed for each two carbon atoms in the water insoluble organic compound containing an active hydrogen with which it is condensed. However, the optimum amount of alkylene oxide can readily be determined in any particular case by preliminary test.

As previously stated, the non-ionic polyglycol ether type detergents derived from alkyl phenolic compounds are particularly valuable in compositions comprising a mixture of such non-ionic detergents and solid inorganic alkalies and are particularly subject to discoloration in such mixtures. Therefore, the poly-alkylene oxide derivatives of such phenolic compounds are a preferred type of non-ionic surface active agents which are employed in the compositions of the present invention. Numerous compounds of this type, i. e. poly-alkylene oxide derivatives of phenolic compounds containing one or more alkyl substituents, which may be employed in the compositions of the present invention are described in U. S. Patent 2,213,477, and I preferably employ the water soluble poly-alkylene oxide derivatives of alkyl phenolic compounds in which the total number of alkyl carbon atoms is between 6 and 18. As examples of such phenolic compounds may be mentioned the isomeric dibutyl and diamyl phenols and cresols, tripropyl phenol and cresol, secondary or tertiary isomeric heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tetradecyl, cetyl, oleyl, octadecyl and the like phenols and cresols. Of particular value are the poly-alkylene oxide derivatives of secondary and tertiary alkyl substituted phenols and cresols obtained by condensing olenes of the type obtained in petroleum refining with phenols or cresols. In the case of products obtained by condensing phenol or cresol with oleiines of from 3 to 5 carbon atoms such as propylene, butylene and amylene, it is desirable to employ the dialkylated phenols or cresols, while in the case or cresol with an olene containing 8 vor more carbon atoms, the mono-substituted derivatives are preferred. Particularly desirable derivatives can be obtained from the phenols and cresols containing a substituent derived from oleflnes containing from 8 to 18 carbon atoms, such as di-isobutylene and other alkylenes as nonylene, decylene, undecylene and dodecylene, pentadecylene, octadecylene and mixtures thereof, and may advantageously be the dimers and trimers obtained by polymerization of such low molecular weight olenes as propylene, butylene, amylene or mixtures thereof. However, the water soluble poly-alkylene oxide derivatives of other water insoluble organic compounds containing at least 6 carbon atoms and having an active hydrogen may be employed in the compositions of the present invention. Thus, the poly-alkylene oxide derivatives, described in U. S. Patent 1,970,578, of aliphatic organic hydroxy compounds, carboxy compounds and amino compounds, as well as phenolic compounds, may be employed if desired. As examples of water insoluble higher fatty acids whose poly-alkylene oxide derivatives may be employed may be mentioned lauric, oleic, ricinoleic, palmitic and stearic acid, and the like, or mixtures thereof, such as the mixtures obtained from animal and vegetable fats and oils or by the oxidation of such petroleum fractions as paraffin wax. There may also be employed poly-alkylene oxide derivatives of water insoluble aliphatic hydroxy compounds such as higher aliphatic alcohols, i. e. the alcohols corresponding to the fatty acids specilied immediately above, particularly the alcohols obtainable by hydrogenation of the fatty acids or glycerides present in animal or vegetable oils and waxes such as cocoanut oil, castor oil and the like. There may also be used polyalkylene oxide derivatives of higher molecular weight amines such as octyl amine, cetyl amine, oleyl amine, naphthyl amines, alkyl anilines, etc.; also the poly-alkylene oxide ,derivatives of organic mercapto compounds such as the products described in U. S. Patent 2,205,021, i. e. the polyalkylene oxide derivatives of such mercapto compounds as dodecyl mercaptan, oleyl mercaptan, cetyl mercaptan, decyl mercaptan and thiophenols, thionaphthols, benzo-mercaptan, etc.; also the poly-alkylene oxide derivatives, such as those described in U. S. Patent 2,085,706, of carboxylic acid amides and of sulfonamides of the type described in U. S. Patent 2,002,613, or the poly-alkylene oxide derivatives, described in U. S. Patent 2,266,141, of sulfonic acids may be employed if desired.

We claim:

1. A color stabilized detergent composition, consisting essentially of a mixture of 99 to 50 percent by weight of solid alkali metal hydroxide selected from the `group consisting of sodium hydroxide and potassium hydroxide and 1 to 50 percent of a mixture consisting essentially of about of a water soluble, non-ionic, surface active agent having a polyglycol ether radical and about 10 percent of thiourea.

2. A composition as deiined in claim 1, wherein the non-ionic detergent specied is a polyglycol ether of an alkyl phenol.

3. A color stabilized detergent composition consisting essentially of a mixture of about percent by weight of solid sodium hydroxide, about 5 percent of a Water-soluble non-ionic surface-active agent said non-ionic surface-active agent being a polyglycol ether of an alkyl phenol containing from 6 to 18 alkyl carbon atoms 6 and in which the polyglycol ether group contains UNITED STATES PATENTS about 1 ethyleneoxy group for each 2 carbon atoms in said alkyl phenol and about 0.5 percent gli Hoyr ApLDgaelgl of thiourea" 2,461,228 Miles Feb 3, 1949 HERBERT L, SANDERS, D OTHER REFERENCES WILLIAM J. MAXCY- Triton NE, Booklet of Rohm & Haas Co., Phila.,

(1943), pgs. 4, 5 and 13. REFERENCES CITED Practical Emulsions, Bennett, Chem. Pub. Co., The following references are of record n the l0 N- Y- (1943), Dg 112- le of this patent: College Chemistry, Smith, 6th ed. (1946), pg. 

1. A COLOR STABILIZED DETERGENT COMPOSITION, CONSISTING ESSENTIALLY OF A MIXTURE OF 99 TO 50 PERCENT BY WEIGHT OF SOLID ALKALI METAL HYDROXIDE SELECTED FROM THE GROUP CONSISTING OF SODIUM HYDROXIDE AND POTASSIUM HYDROXIDE AND 1 TO 50 PERCENT OF A MIXTURE CONSISTING ESSENTIALLY OF ABOUT 90% OF A WATER SOLUBLE, NON-IONIC, SURFACE ACTIVE AGENT HAVING A POLYGLYCOL ETHER RADICAL AND ABOUT 10 PERCENT OF THIOUREA. 